Improvement in screw-drivers



W. `l". PATTERSON.

Screw-Drivers.

Patented Feb. 24.1874.

UNITED STATES- PATENT Crmon.

WILLIAM F. PATTERSON, OF BOSTON, MASSACHUSETTS.

IMFI-'OVIVIENT` IN SCREW-DRIVERS.

v Specification forming part of Letters Patent No. 147,785, dated February 24, 1874; application filed October 10, 1873.

To all whom t may concern:

Be it known that I, WILLIAM F. PATTER- soN, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Screw- Drivers; and I do hereby declare the following to be a full, clear, and exa-ct description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to iml'irovements in screw-drivers; and consists in making the blades pointed or tapering at each end, so as to be reversible; also, in the employment of two drivers, of which one projects beyond the other, in one and the same handle; and also' in the employment of a stationary or adjustvable step inside of the blade-case, on which 011e of the blades is supported and held in place. The blades are kept in a split case, provided in its upper end with a conical screw-thread, over which is fitted a conical screw-cap, by means of which the blades are held lirmly in place in the split case.

On the drawings, Figure l represents a side elevation of my improved screw-driver. Fig. 2 represents a central longitudinal section of the same. Fig. 3 represents a front vie-w of one of the blades; and Fig. et represents a cross-section on the lineA B, shown in Fig. 1.

Similar letters refer to similar parts wherever they occur in the drawing.

a represents the handle, in which the case or blade-holder bis secured, as shown in Figs.

l and 2. The said case or blade-holder is made in two parts, the upper ends of which are out with a conica-l screw-thread, c, around which is fitted the conical screw-threaded sleeve or nut d, as shown. Two screw-drivers, c e', may be used, and secured in the case b in such a manner that one of them is made to project beyond the others when used, which is accomplished by means of a movable or stationary step, f, arranged in the lower part of the case b, upon which the driver rests that is in use. The step f may be made movable in the case b, having for that purpose a pin, g, put through it and secured to it, as shown in Figs. 2 and 4. The pin g is movable in holes made in the case b b, by which arrangement the said step f may be moved from one side to another in the case b, for the purpose of allowing any one of the drivers e c to project beyond the other. Each of the screwdrivers e e is provided at each end with a tapering part, as shown in Fig. 3, so that each end can be used as a screw-driver, by which construction I obtain the advantage of having two screw-drivers of different sizes on one and the same blade; consequently, with two blades, c e', arranged in the case Z1 b; as shown, I obtain the advantage of four distinct screwdrivers of different sizes. All the blades e ef in the case b b may be made of equal length; but it is necessary that the blade that is used should project alittle beyond the others, as shown in Figs. 1 and 2.

With two blades, ce', held in the case b b, I am thus able to operate a great many of the different sizes of screws that are ordinarily used, in one tool, not larger than one ordinary screw-driver. II' any desired blade is to be changed, all that is required to be done is to unser-ew the nut d, and place the driver that is to be used on the step j', and let the other one sink down lower in the case b b, as shown in Fig. 2, after which the nutd may be screwed over the screw-threaded pieces c c, and thus secure the blades firmly in their respective places in the case I) b.

Havingthus fully described the nature, construction, and operation of my invention, I wish to secure by Letters Patent, and claim- The reversible and detachable blades e e', either one of which is arranged to project beyond the other, in combination with the handle Z) b, provided with the threaded bosses c c, conical nut d, and stationary or adjustable step f, substantiallyin the manner and for the purpose speeied.

In testimony that I claim the foregoing' I have hereunto set my hand this 30th day of September, 1873.

VILLIAM F. PATTERSON.

Witnesses y ALBAN ANDRN, GEORGE E. PIIELPs. 

